xenial (1) xss-lock.1.gz

NAME

       xss-lock - use external locker as X screen saver

SYNOPSIS

       xss-lock [-n notify_cmd] [--ignore-sleep] [-l] [-v|-q] [--] locker [arg] ...
       xss-lock --help|--version

DESCRIPTION

       xss-lock  hooks  up  your  favorite  locker to the MIT screen saver extension for X and also to systemd's
       login manager. The locker is executed in response to events from these two sources:

       • X signals when screen saver activation is forced or after a period of user inactivity (as set with xset
         s TIMEOUT). In the latter case, the notifier command, if specified, is executed first.

       • The  login  manager can also request that the session be locked; as a result of loginctl lock-sessions,
         for example. Additionally, xss-lock uses the inhibition logic to lock the screen before the system goes
         to sleep.

       xss-lock  waits for the locker to exit -- or kills it when screen saver deactivation or session unlocking
       is forced -- so the command should not fork.

       Also, xss-lock manages the idle hint on the login session. The idle state  of  the  session  is  directly
       linked  to user activity as reported by X (except when the notifier runs before locking the screen). When
       all sessions are idle, the login manager can  take  action  (such  as  suspending  the  system)  after  a
       preconfigured delay.

OPTIONS

       -n cmd, --notifier=cmd
              Run  cmd  when  the  screen  saver  activates  because  of user inactivity. Shell-style quoting is
              supported. The notifier is killed when X signals user activity or when the locker is started.  The
              locker is started after the first screen saver cycle, as set with xset s TIMEOUT CYCLE.

              This can be used to run a countdown or (on laptops) dim the screen before locking. For an example,
              see the script /usr/share/doc/xss-lock/dim-screen.sh.

       -l, --tranfer-sleep-lock
              Allow the locker process to inherit the file descriptor that represents the  delay  lock  obtained
              from the login manager. The corresponding index will be made available in the environment variable
              $XSS_SLEEP_LOCK_FD; this will only be set if  the  reason  for  locking  is  that  the  system  is
              preparing to go to sleep. The locker should close this file descriptor to indicate it is ready.

              Example      scripts      that      wrap      existing      lockers      are      available     as
              /usr/share/doc/xss-lock/transfer-sleep-lock-*.sh.

       --ignore-sleep
              Do not lock on suspend/hibernate.

       -q, --quiet
              Output only fatal errors.

       -v, --verbose
              Output more messages.

       -h, --help
              Print help message and exit.

       --version
              Print version number and exit.

SIGNALS

       SIGHUP Upon receiving this signal, xss-lock resets the screen saver,  but  only  if  the  screen  is  not
              currently locked (unlike xset s reset).

              This  can  be used in MPlayer's configuration as a workaround for MPlayer's failure to restart the
              screen saver timer when playback is paused:

                 heartbeat-cmd="killall -HUP xss-lock"
                 stop-xscreensaver=false

              NOTE:
                 This is ineffective with mplayer2 (and mpv), because its heart keeps beating while playback  is
                 paused.

       SIGINT/SIGTERM
              Upon receiving this signal, xss-lock exits after killing any running notifier or locker.

NOTES

       • Some  applications  rely on the xdg-screensaver script from xdg-utils, which uses xset s off and xset s
         default to suspend and resume the screen saver, respectively. The latter resets the timeout  and  cycle
         to  the  server  defaults  (xset  s on uses a hardcoded default instead), so this only works if you are
         happy with (or can control) the server settings.

         To fix the resume action in this script (or a copy in ~/bin preceding the original  in  $PATH),  either
         replace  on  by your preferred timeout and cycle, or avoid hardcoded time values by patching the script
         to    run    a    suspend    loop    as    it    does    for     other     screen     savers,     using
         /usr/share/doc/xss-lock/xdg-screensaver.patch.

EXAMPLES

       • Run xlock after ten minutes of inactivity:

            xset 600
            xss-lock xlock +resetsaver

         Without  +resetsaver,  xlock  forces  a  screen saver reset during startup, thereby telling xss-lock to
         immediately kill xlock again.

       • Dim the screen after three minutes of inactivity, lock the screen two minutes later using i3lock:

            xset 180 120
            xss-lock -n dim-screen.sh -- i3lock -n

         NOTE:
            A script is provided to use i3lock's forking mode with the --tranfer-sleep-lock option (see above).

SEE ALSO

       xset(1), systemd-logind.service(8)

AUTHOR

       Raymond Wagenmaker <raymondwagenmaker@gmail.com>

                                                  November 2013                                      XSS-LOCK(1)